We wish to examine electron transfer characteristics of Fe-S proteins including ferredoxins, hydrogenase, glutamate synthase, and to develop pulsed EPR techniques for structural studies of paramagnetic enzymes. We propose to study both the activation (by ACTH) and mechanism of P-450scc in adrenal cortical mitochondria. We have purified the enzymes of H2 uptake in methane-producing bacteria and are examining their mechanisms. We use EPR, Mossbauer, and optical spectroscopy in this work. We have also uncovered a novel phenomenon, namely Cu ions uptake and processing by lymphocytes entering blastogenesis. We propose to explore the biochemical basis of this early event in secondary immune response.